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2391. SOFIA Horsehead nebula region datacube
ID:
ivo://CDS.VizieR/J/A+A/595/A34
Title:
SOFIA Horsehead nebula region datacube
Short Name:
J/A+A/595/A34
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new multi-pixel high resolution (R>~10^7^) spectrometer for the Stratospheric Observatory for far-infrared astronomy (SOFIA). The receiver uses 2x7-pixel subarrays in orthogonal polarization, each in an hexagonal array around a central pixel. We present the first results for this new instrument after commissioning campaigns in May and December 2015 and after science observations performed in May 2016. The receiver is designed to ultimately cover the full 1.8-2.5THz frequency range but in its first implementation, the observing range was limited to observations of the [CII] line at 1.9THz in 2015 and extended to 1.83-2.07THz in 2016. The instrument sensitivities are state-of-the-art and the first scientific observations performed shortly after the commissioning confirm that the time electronic efficiency for large scale imaging is improved by more than an order of magnitude as compared to single pixel receivers. An example of large scale mapping around the Horsehead Nebula is presented here illustrating this improvement. The array has been added to SOFIA's instrument suite already for ongoing observing cycle 4.
2392. SOFIA Massive (SOMA) Star Formation Survey. I.
ID:
ivo://CDS.VizieR/J/ApJ/843/33
Title:
SOFIA Massive (SOMA) Star Formation Survey. I.
Short Name:
J/ApJ/843/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an overview and first results of the Stratospheric Observatory For Infrared Astronomy Massive (SOMA) Star Formation Survey, which is using the FORCAST instrument to image massive protostars from ~10 to 40{mu}m. These wavelengths trace thermal emission from warm dust, which in Core Accretion models mainly emerges from the inner regions of protostellar outflow cavities. Dust in dense core envelopes also imprints characteristic extinction patterns at these wavelengths, causing intensity peaks to shift along the outflow axis and profiles to become more symmetric at longer wavelengths. We present observational results for the first eight protostars in the survey, i.e., multiwavelength images, including some ancillary ground-based mid- infrared (MIR) observations and archival Spitzer and Herschel data. These images generally show extended MIR/FIR emission along directions consistent with those of known outflows and with shorter wavelength peak flux positions displaced from the protostar along the blueshifted, near-facing sides, thus confirming qualitative predictions of Core Accretion models. We then compile spectral energy distributions and use these to derive protostellar properties by fitting theoretical radiative transfer models. Zhang and Tan models, based on the Turbulent Core Model of McKee and Tan, imply the sources have protostellar masses m*~10-50M_{sun}_ accreting at ~10^-4^-10^-3^M_{sun}_/yr inside cores of initial masses Mc~30-500M_{sun}_ embedded in clumps with mass surface densities {Sigma}_cl_~0.1-3g/cm^2^. Fitting the Robitaille et al. models typically leads to slightly higher protostellar masses, but with disk accretion rates ~100x smaller. We discuss reasons for these differences and overall implications of these first survey results for massive star formation theories.
2393. SOIR
ID:
ivo://bira-iasb/soir/soir_q/epn_core
Title:
SOIR
Short Name:
soir.epn_core
Date:
08 Oct 2024 09:26:16
Publisher:
Planetary Atmospheres Research Unit - Royal Belgian Institute for Space Aeronomy
Description:
Profiles of species in Venus atmosphere terminator. Data retrieved from calibrated spectra obtained with the SPICAV-SOIR instrument on board the Venus Express spacecraft. These spectra can be checked on the ESA PSA repository. See: A.C. Vandaele et al., Contribution from SOIR/VEX to the updated Venus International Reference Atmosphere (VIRA), Adv. Space Res. (2015), http://dx.doi.org/10.1016/j.asr:2015.08.012.
2394. Solar disk spectrum (660-1175A)
ID:
ivo://CDS.VizieR/J/A+AS/126/281
Title:
Solar disk spectrum (660-1175A)
Short Name:
J/A+AS/126/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
The near-limb quiet-Sun spectrum recorded on January 25, 1996 near the solar North pole is presented in tabular form and in graphical form. Table 1 - the line list - lists all lines found in the spectrum providing absolute peak intensities, measured and literature wavelengths, identification, and classification of the transition. Fig. 4 is a display the composite spectrum. The most prominent lines are labelled. In this figure intensities are given in instrumental units and logarithmic scale.
2395. Solar flux model in 30-1300nm wavelength range
ID:
ivo://CDS.VizieR/J/ApJS/181/351
Title:
Solar flux model in 30-1300nm wavelength range
Short Name:
J/ApJS/181/351
Date:
21 Oct 2021
Publisher:
CDS
Description:
Solar photon scattering probabilities (g values) have been calculated for discrete transitions in 12 species, in a format designed primarily to allow analysis of spacecraft observations from MESSENGER and BepiColombo at Mercury. The results support observations using the MESSENGER Ultraviolet and Visible Spectrometer spectrograph experiment operating over the spectral range 1150-6000{AA} and the BepiColombo spectrograph in the range 550-3150{AA}. Significant radial velocity dependence is shown for most of the emission lines, a critical factor for interpretation of the observed spectra. The g values have general application for solar system emission sources dominated by scattering of the solar flux.
2396. SOLAR-ISS Spectrum covering 165-3000nm
ID:
ivo://CDS.VizieR/J/other/SoPh/295.14
Title:
SOLAR-ISS Spectrum covering 165-3000nm
Short Name:
J/other/SoPh/295
Date:
21 Oct 2021
Publisher:
CDS
Description:
The accurate measurement of the solar spectrum at the top of the atmosphere and its variability are fundamental inputs for solar physics (Sun modeling), terrestrial atmospheric photochemistry, and Earth's climate (climate's modeling). These inputs were the prime objective set in 1996 for the SOLAR International Space Station (ISS). The SOLAR package represents a set of three solar instruments measuring the total and spectral absolute irradiance from 16nm to 3088nm. SOLAR was launched with the European Columbus space laboratory in February 2008 aboard the NASA Space Shuttle Atlantis. SOLAR on the ISS tracked the Sun until it was decommissioned in February 2017. The SOLar SPECtrum (SOLSPEC) instrument of the SOLAR payload allowed the measurement of solar spectra in the 165-3000nm wavelength range for almost a decade. Until the end of its mission, SOLAR/SOLSPEC was pushed to its limits to test how it was affected by space environmental effects (external thermal factors) and to better calibrate the space-based spectrometer. To that end, a new solar reference spectrum (SOLAR-ISS - V1.1) representative of the 2008 solar minimum was obtained from the measurements made by the SOLAR/SOLSPEC instrument and its calibrations. The main purpose of this article is to improve the SOLAR-ISS reference spectrum (between 165 and 180nm in the far ultraviolet, between 216.9 and 226.8nm in the middle ultraviolet, and between 2400 and 3000nm in the near-infrared). SOLAR-ISS has a resolution better than 0.1nm between 165 and 1000nm, and 1nm in the 1000-3000nm wavelength range. Finally, a first comparison is made between the new SOLAR-ISS spectrum (V2.0) and the Total and Spectral solar Irradiance Sensor (TSIS-1) spectrum obtained from its first observations from the ISS. Indeed, the launch of TSIS in December 2017 provides a new light on the absolute determination of the solar spectrum and especially in the infrared region of the spectrum.
2397. Solar lines from Ceres spectra
ID:
ivo://CDS.VizieR/J/A+A/544/A125
Title:
Solar lines from Ceres spectra
Short Name:
J/A+A/544/A125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Present knowledge of the solar spectrum is limited because it is very difficult to observe the integrated solar spectrum at high resolution. The reflected solar light from asteroids has been shown to provide a relatively straightforward integrated and unmodified solar spectrum. We exploit this methodology to improve our knowledge of solar photospheric line positions both in terms of line number and precision with respect to the available solar line atlas.
2398. Solar Lyman irradiance line profiles
ID:
ivo://CDS.VizieR/J/A+A/581/A26
Title:
Solar Lyman irradiance line profiles
Short Name:
J/A+A/581/A26
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate hydrogen spectra emitted by the entire solar disc in the Ly-{alpha} and Ly-{beta} lines are valuable for deriving the distribution and the behaviour of atomic hydrogen in the heliosphere, for understanding the UV emissions of solar type stars better, and finally for estimating the solar energy input that mainly initiates the chemical processes occurring in the planetary and cometary outer atmospheres. In this paper we want to accurately determine the irradiance solar spectral profiles of Ly-{alpha} and Ly-{beta} and their evolution through the solar activity cycle 23. The SUMER/SOHO spectrometer is a slit spectrometer that is only able to analyse a small part of the solar image. Consequently, we used the scattered light properties of the telescope to obtain average spectra over the solar disc. Then the profile is calibrated using the SOLSTICE/UARS and TIMED/SEE irradiance spectra.
2399. SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm
ID:
ivo://CDS.VizieR/J/A+A/611/A1
Title:
SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm
Short Name:
J/A+A/611/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1{sigma} from 165 to 3000nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5nm in the 165-3000nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1nm below 1000nm and 1nm in the 1000-3000nm wavelength range. The new solar spectrum (SOLAR-ISS) highlights significant differences with previous solar reference spectra and with solar spectra based on models. The integral of the SOLAR-ISS solar spectrum yields a total solar irradiance of 1372.3+/-16.9W/m^2^ at 1{sigma}, that is yet 11W/m^2^ over the value recommended by the International Astronomical Union in 2015.
2400. SOLAR/SOLSPEC UV SSI from 2008-2015
ID:
ivo://CDS.VizieR/J/other/SoPh/291.3527
Title:
SOLAR/SOLSPEC UV SSI from 2008-2015
Short Name:
J/other/SoPh/291
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate measurements of the solar spectral irradiance (SSI) and its temporal variations are of primary interest to better understand solar mechanisms, and the links between solar variability and Earth's atmosphere and climate. The SOLar SPECtrum (SOLSPEC) instrument of the Solar Monitoring Observatory (SOLAR) payload onboard the International Space Station (ISS) has been built to carry out SSI measurements from 165 to 3088nm. We focus here on the ultraviolet (UV) part of the measured solar spectrum (wavelengths less than 400 nm) because the UV part is potentially important for understanding the solar forcing of Earth's atmosphere and climate. We present here SOLAR/SOLSPEC UV data obtained since 2008, and their variations in three spectral bands during Solar Cycle 24. They are compared with previously reported UV measurements and model reconstructions, and differences are discussed.

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